46/150: Earthworms – Westward Ho!

Happy Earth Day! Let’s talk about earthworms! Although they are found in many gardens and forests in Canada today, earthworms such as Dendrobaena octaedra are not actually native to this country. In fact, their movement and establishment to North America can be traced to early settlers from Europe, who may have either brought worms for agricultural benefits or accidentally in ship ballasts. Before this, Canadian forests were free of earthworms, and the continuing Western expansions of species that dwell in the soil and leaf litter are a detriment to these habitats. D. octaedra and other earthworms consume the layer of decomposing organic matter and mix soil layers in these forests which can reduce numbers of small invertebrates found in those soils and can disrupt the growth of saplings. There are currently 246 specimens of D. octaedra with barcodes on BOLD. #Canada150 #Biodiversity150

Specimen 09BBANN-074 – Kejimkujik National Park – 01-Aug-2009. Photo Credit: CBG Photography Group, Centre for Biodiversity GenomicsEarthworm head anatomy, showing the relative complexity of an organism we consider quite simple. Photo Credit: KDS4444 goo.gl/AatnJMCocoons of Lumbricus terrestris, another invasive earthworm, which are commonly found in leaf litter, can be trapped in vehicle tires, which expedite their movement. Photo Credit: Clive A. Edwards, Ohio State University goo.gl/nG1lij

45/150: Cephalopods are Insane in the Membrane

The opalescent inshore squid, Dorytheuthis opalescens, can be found along the Pacific coast from Alaska to Mexico. They are part of the myopsid squids, meaning that they have a cornea unlike other cephalopods as it is covered in a corneal membrane instead of a second eyelid. Popular as a common market squid as calamari, these cephalopods inhabit inshore waters (as their common name suggests). Squids also possess chromatophores, pigment or reflection cells, within their skin. This can be used as a type of camouflage to protect them from predation. Because chromatophores are controlled via muscle contraction, scientists at the Marine Biological Laboratory in Massachusetts found that these cells could be controlled by music! By cutting off the earbuds and connection the wire directly to the skin, music with bass frequencies cause the chromatophores to activate. #Canada150 #Biodiversity150

Check out this incredible video of squid chromatophores “dancing” to Insane in the Membrane by Cypress Hill

D. opalescens moseying about, displaying its typically iridescence. Photo Credit: Joshua Sera goo.gl/9AtHHrD. opalescens flaring up its chromatophores in order to mimic sand. You are able to see xanthophores (yellow), erythrophores (red), and melanophores (black/brown). Photo Credit: Minette goo.gl/v7w86AThe very very small paralarvae, or hatchling, of D. opalescens. Photo Credit: Todd Anderson goo.gl/rdWh3G